A large number of households have one or more animal pets. Domestic cats in particular are estimated to live in over thirty million homes all or most of the day. A litter box or the like is a necessity for such homes. In fact, basic litter boxes which are rectangular-shaped with a height of about four to five inches have been used for many years. While much development work has been expended in producing improved litter material to make it more absorbent, odor-free, dust-free, etc., very little change has occurred in the basic litter box itself. Those boxes being presently commercialized are remarkably similar to those of several years ago.
Maintaining pet litter boxes requires frequent cleaning and attention. This job is unpleasant due to odor. Strong odor and unsanitary conditions develop quickly if the pet litter box is not properly maintained on a frequent basis. Busy schedules and travel make proper attention to the pet litter boxes difficult.
Conventional litter boxes are popular simply because they have proven themselves effective. Cats are readily trained to use them. The biggest drawback associated with the conventional litter box is a need to periodically remove soiled litter material and replenish it with new litter material. Any cat owner will attest to the fact cats are fastidious. They will not use a litter box which contains what they consider an excessive amount of soiled litter material. The cat owner can at that point simply dump the full contents of the litter box into the trash or otherwise dispose of it. This, of course, is wasteful and expensive in that a substantial amount of unsoiled litter material is being disposed of along with the soiled litter material. It is more common for the cat owner to try to segregate soiled from unsoiled litter material. This is possible because most litter materials are designed to clump when wetted. Various scoops are sold for this purpose. However, the task of scooping clumped soiled litter material and cat feces from a litter box is still an arduous and unpleasant task.
The problem with cleaning and keeping the contents of a litter box in a state which is acceptable to the cat is well recognized. Several attempts have been made over the years to remedy the problem. U.S. Pat. Nos. 4,846,104, 5,048,464, and 5,662,066 contain disclosures of self-cleaning pet litter box systems wherein specially configured spherical or cylindrical containers rotate in a manner to separate clumped from unclumped litter material. U.S. Pat. Nos. 4,574,735, 5,048,465 and 5,477,812 also disclose self-cleaning pet litter box systems. Basically, the systems have a stationary litter container and a rake or comb-type device that periodically moves through litter in the container to separate out clumped material. The clumped material is directed to a separate disposal system as part of the process.
Applicant has developed a self-cleaning pet litter box assembly which overcomes known problems and disadvantages of prior self-cleaning pet litter box systems as fully described in Applicant's U.S. Pat. Nos. 6,234,112 and 6,401,661, which disclosures are hereby incorporated herein by reference. The self-cleaning pet litter box assembly described in these patents is motor driven to rotate and during the rotation segregate clumped material and solid pet waste from unclumped litter material. The assembly comprises a base member with a pet litter container mounted thereon for horizontal rotational movement. A motor is mounted on the base member or other locations and is operatively connected to the litter container to slowly and continuously rotate the container. However, the litter container could also be rotated periodically, or at various rates of speed. The assembly also includes a separating member and a conveyor. The separating member extends into the litter within the litter container. As the litter container rotates, clumped and unclumped litter material and solid pet waste move into contact with the separating member. Unclumped litter passes through the separating member and remains in the litter container for reuse. Soiled clumped litter and solid pet waste is directed toward the conveyor by the separating member where they are conveyed away to a waste receptacle. The pet owner periodically must empty or replace the waste receptacle, however, the task is less often and not as unpleasant as before.
While Applicant's self-cleaning pet litter box assembly as described in U.S. Pat. Nos. 6,234,112 and 6,401,661 overcomes the known drawbacks and disadvantages of prior self-cleaning pet litter box systems, there is an on going need for improvements in self-cleaning pet litter box assemblies to effectively separate and remove pet waste and soiled pet litter from unclumped litter material in the pet litter container.